The cause of this disease is due to attack by pathogenic dampness and heat. The pathogenic factors may come from urinary bladder itself, or transmitted from other viscera. The pathogenesis mainly lies in the fact that accumulation of dampness and heat in the lower energizer causes unsmooth qi activity of urinary bladder. The kidney and urinary bladder are exteriorly-interiorly related. Therefore, asthenia of the kidney results in invasion of exogenous pathogenic factors.

Besides, dampness and heat in the urinary bladder rise reversely, make both zang organ and fu organ diseased, giving rise to abnormal qi activity of urinary bladder and obstructed water circulation. In this case, frequent and urgent urination as well as dysuria with dribbling urine occurs. Pathogenic factors struggle with body resistance, giving rise to shiver and high fever. When dampness obstructs middle energizer, accompaying symptoms of poor appetite, vomiting and diarrhea may occur.